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Antibiotics (Basel, Switzerland) Apr 2021spp. are emerging pathogens mainly in nosocomial infections. in particular is involved in urinary tract infections and contributes significantly to the high incidence...
spp. are emerging pathogens mainly in nosocomial infections. in particular is involved in urinary tract infections and contributes significantly to the high incidence of biofilm-formation in catheterized patients. Furthermore, recent reports suggested a role for multiple drug resistant (MDR) in hospital-associated outbreaks which leads to excessive complications resulting in challenging treatments. Phage therapy is currently one of the most promising solutions to combat antibiotic-resistant infections. However, the number of available phages targeting spp. is extremely limited, restricting the use of phage therapy in such cases. In the present study, we describe the isolation and characterization of 17 lytic and temperate bacteriophages targeting clinical isolates of spp. as part of the Israeli Phage Bank (IPB). These phages, isolated from sewage samples, were evaluated for host range activity and effectively eradicated 95% of the tested bacterial strains isolated from different geographic locations and displaying a wide range of antibiotic resistance. Their lytic activity is demonstrated on agar plates, planktonic cultures, and biofilm formed in a catheter model. The results suggest that these bacteriophages can potentially be used for treatment of antibiotic-resistant spp. infections in general and of urinary tract infections in particular.
PubMed: 33918377
DOI: 10.3390/antibiotics10040375 -
BMC Complementary Medicine and Therapies Jul 2022The rise of multidrug-resistant (MDR) bacteria is a real public health problem worldwide and is responsible for the increase in hospital infections. Donella welwitschii...
BACKGROUND
The rise of multidrug-resistant (MDR) bacteria is a real public health problem worldwide and is responsible for the increase in hospital infections. Donella welwitschii is a liana or shrub belonging to the family Sapotaceae and traditionally used to cure coughs.
OBJECTIVE
This study was conducted with the objective to validate the medicinal properties of this plant, the aerial part was studied for its phytochemical composition using column and PTLC chromatography and exploring its antibacterial and antibiotic-modifying activity as well as those of its phytochemicals.
METHODS
The structures of the compounds were elucidated from their physical and spectroscopic data in conjunction with literature. The antibacterial activity of the isolated metabolites was performed toward a panel of MDR Gram negative and Gram-positive bacteria. The broth micro-dilution method was used to determine antibacterial activities, efflux pump effect using the efflux pump inhibitor (EPI) (phenylalanine-arginine-ß-naphthylamide (PAβN)), as well as the modulating activity of antibiotics. Monitoring the acidification of the bacterial growth medium was used to study the effects of the samples on the bacterial proton-ATPase pumps and cellular ATP production.
RESULTS
Eleven compounds were isolated including pentacyclic triterpenes, C-glucosyl benzophenones. With a MIC value < 10 μg/mL, diospyric acid (7) significantly inhibited the growth of Escherichia coli AG102, Enterobacter aerogenes ATCC13048, Klebsiella pneumoniae KP55, Providencia stuartii NEA16 and Staphylococcus aureus MRSA3. 28-hydroxy-β-amyrin (8) significantly impaired the growth of Enterobacter aerogenes EA27, Klebsiella pneumoniae ATCC11296 and Staphylococcus aureus MRSA6; and oleanolic acid (9) strongly impaired the growth of Escherichia coli AG 102, Enterobacter aerogenes EA27 and Providencia stuartii PS2636. Diospyric acid (7) and 28-hydroxy-β-amyrin (8) induced perturbation of H-ATPase pump and inhibition of the cellular ATP production. Moreover, at MIC/2 and MIC/4, compounds 7, 8, and 9 strongly improved the antibacterial activity of norfloxacin, ciprofloxacin and doxycycline with antibiotic-modulating factors ranging between 2 and 64.
CONCLUSION
The overall results of the current work demonstrate that diospyric acid (7), 28-hydroxy-β-amyrin (8) and oleanolic acid (9) are the major bioactive constituents of Donella welwitschia towards Gram-negative bacteria expressing MDR phenotypes.
Topics: Adenosine Triphosphate; Anti-Bacterial Agents; Escherichia coli; Microbial Sensitivity Tests; Oleanolic Acid; Phenotype; Phytochemicals; Plant Components, Aerial; Plant Extracts; Providencia; Sapotaceae
PubMed: 35858857
DOI: 10.1186/s12906-022-03673-3 -
Revista Chilena de Pediatria Feb 2020Infant mortality depends on the economic, social, and cultural level of development of the place of residence.
INTRODUCTION
Infant mortality depends on the economic, social, and cultural level of development of the place of residence.
OBJECTIVE
To describe the infant mortality rates (IMR) and the late infant mortality rates (LIMR) of the Metropolitan Region (MR) communes and to evaluate their trend between 2005 and 2014.
MATERIAL AND METHOD
Ecological study that describes the rates of the 52 communes of the MR. For the analysis, the IMR and LIMR were elaborated for each year and com mune and were compared using population attributable risk (PAR), attributable risk percent (AR%), and rate ratio (RR). Trends were analyzed through the Prais-Winsten model. A value p < 0.05 was considered a statistically significant trend.
RESULTS
The commune 'Independencia' presented the hig hest IMR and LIMR with 12.7 and 4.05 per 1000 live births respectively, 1.75 and 2.05 times more compared with the IMR and LIMR of the MR. The commune 'Las Condes' and 'Vitacura' presented the lowest IMR and LIMR respectively. The IMR trend regarding 2005 increased in Lo Barnechea, Lo Espejo, and Recoleta, and decreased in Las Condes, Macul, Pudahuel and San Bernardo. The LIMR decreased in Peñalolén, Puente Alto, Las Condes, Providencia, San Bernardo, Macul, Pudahuel, Tala- gante, Pedro Aguirre Cerda, and Quilicura, and increased in Peñaflor.
CONCLUSION
The regional IMR and LIMR hide the slight increase in rates and the persistence of heterogeneity among communes. This forces us to explore the causes of these inequities through future analytical studies.
Topics: Chile; Health Status Disparities; Humans; Infant; Infant Mortality; Infant, Newborn; Urban Health
PubMed: 32730411
DOI: 10.32641/rchped.v91i1.1205 -
JAAD Case Reports May 2020
PubMed: 32382635
DOI: 10.1016/j.jdcr.2020.02.043 -
The Indian Journal of Medical Research Aug 2023During the course of a retrospective survey on healthcare associated infections (HAIs) due to carbapenem-resistant organisms, an unusual prevalence of HAIs due to...
BACKGROUND & OBJECTIVES
During the course of a retrospective survey on healthcare associated infections (HAIs) due to carbapenem-resistant organisms, an unusual prevalence of HAIs due to carbapenem-resistant Providencia stuartii (CRPS) was found. Hence this study aimed to conduct the occurrence of P. stuartii associated HAIs with special reference to the drug resistance profiling of these isolates.
METHODS
Of the eight total HAI cases (7.5% of total HAIs and 33.3% of HAIs due to Enterobacterales) of CRPS infections included in this study, three were reported from ventilator-associated pneumonia (VAP), three were surgical site infections (SSIs), one was a catheter-associated urinary tract infection (CAUTI) and one was a bloodstream infection. All the eight CRPS isolates were tested for extended-spectrum β-lactamases production, AmpC hyperproduction as well as carbapenem resistance. Typing of the isolates was performed by repetitive extragenic palindromic polymerase chain reaction (REP-PCR).
RESULTS
All the eight isolates of CRPS were found to be AmpC hyperproducers, carbapenemase producers, and harboured chromosomally located bla in seven isolates and bla genes in one. All the cases with CRPS infections had prior history of colistin therapy along with prolonged hospital stay (>20 days). The cases were located in five different wards/intensive care unit (ICU) within the hospital in one year. However, strain typing by REP-PCR revealed 100 per cent similarity and clonal relatedness in all the seven isolates carrying bla genes. Interestingly, routine hospital surveillance revealed a high carriage of P. stuartii in the axilla of patients admitted to the ICU.
INTERPRETATION & CONCLUSIONS
The study findings suggest CRPS as an important cause of HAIs. This organism often goes unnoticed due to the burden of carbapenem resistance in other Enterobacterales and non-fermenters.
Topics: Humans; Retrospective Studies; Microbial Sensitivity Tests; Bacterial Proteins; beta-Lactamases; Carbapenems; Cross Infection; Hospitals; Anti-Bacterial Agents
PubMed: 37787258
DOI: 10.4103/ijmr.IJMR_3668_20 -
Placenta Sep 2022During pregnancy, the developing foetus requires large amounts of cholesterol from the maternal plasma, which is mediated by proteins such as the receptor for... (Review)
Review
During pregnancy, the developing foetus requires large amounts of cholesterol from the maternal plasma, which is mediated by proteins such as the receptor for low-density lipoproteins (LDLR). The quantity of LDLR available in the syncytiotrophoblast plasma membrane is an important factor for the uptake, metabolism, and transfer of cholesterol to foetal circulation. Because of the relevance of this receptor for cellular and systemic cholesterol metabolism in non-placental cells, the study of mechanisms associated with LDLR trafficking, such as the availability in the cell membrane, endocytosis, recycling, sorting, and degradation, have been extensively studied. Multiple protein groups are required for proper LDL/LDLR trafficking. Changes in the function of these proteins are related to hypercholesterolemia, the main risk factor associated with cardiovascular disease. It is well known that the placenta plays an essential role as a barrier between maternal lipids and the foetus and that imbalances in maternal cholesterol levels during pregnancy are frequent and associated with cardiovascular disease in the offspring. However, there is little information regarding lipoprotein trafficking in this system. In this review, we summarize the available information on LDLR trafficking, emphasizing the few reports related to receptor biology in placental cells from normal and pathological pregnancies. We conclude that extensive research on the cell biology of the placenta is required to unravel the endocytic trafficking of proteins such as LDLR in a highly specialized cell such as the syncytiotrophoblast.
Topics: Cardiovascular Diseases; Cholesterol; Female; Humans; Hypercholesterolemia; Lipoproteins, LDL; Pregnancy; Receptors, LDL; Trophoblasts
PubMed: 35926304
DOI: 10.1016/j.placenta.2022.07.013 -
Molecular Biotechnology Mar 2017Urea in alcoholic beverage is a precursor of ethyl carbamate (EC), which is carcinogenic. Enzymatic elimination of urea has attracted much research interest. Acid urease... (Review)
Review
Urea in alcoholic beverage is a precursor of ethyl carbamate (EC), which is carcinogenic. Enzymatic elimination of urea has attracted much research interest. Acid urease with good tolerance toward ethanol and acid is ideal enzyme for such applications. In the present work, the structural genes of urease from Providencia rettgeri JN-B815, ureABC were efficiently expressed in E. coli BL21(DE3) in an active form (apourease) exhibiting both urease and urethanase (hydrolyze EC) activities. The specific activities of the purified apourease were comparatively low, which were 2.1 U/mg for urease and 0.6 U/mg for urethanase, respectively. However, apourease exhibited good resistance toward ethanol and acidic conditions. The relative activities of urease and urethanase remained over 80% in the buffers within pH 4-7. And the recoveries of both urease and urethanase activities were more than 50% in 5-25% ethanol solution. Apourease was utilized to eliminate urea in wine, and the residual urea in model wine was less than 50% after treatment with apourease for 30 h. Then 3D structure of UreC was predicted, and it was docked with urea and EC, respectively. The docking result revealed that three hydrogen bonds were formed between urea and amino acid residues in the active site of urease, whereas only one hydrogen bond can be formed between EC and the active center. Moreover, EC exhibited greater steric hindrance than urea when combined with the active site. Due to the low specific activities of apourease, both structural genes and accessory genes of urease were co-expressed in E. coli BL21(DE3). The holoenzyme was expressed as inclusion body. After renaturation and purification, the specific activities of urease and urethanase reached 10.7 and 3.8 U/mg, which were 5.62-fold and 6.33-fold of those of apourease, respectively. Therefore, accessory subunits of urease play an important role in enhancing urease and urethanase activities.
Topics: Amidohydrolases; Bacterial Proteins; Cloning, Molecular; Enzyme Stability; Escherichia coli; Holoenzymes; Hydrogen-Ion Concentration; Molecular Docking Simulation; Providencia; Urea; Urease; Wine
PubMed: 28197768
DOI: 10.1007/s12033-017-9994-x -
European Journal of Clinical... May 2024Providencia genus is known to harbor certain opportunistic pathogens capable of causing human infections. Here, we report two strains of multidrug-resistant bacteria...
Providencia genus is known to harbor certain opportunistic pathogens capable of causing human infections. Here, we report two strains of multidrug-resistant bacteria initially identified as Providencia rettgeri by mass spectrometry, but genome analysis revealed their ANI (79.84-84.20%) and dDDH (21.1-25.6%) values to fall below the accepted species threshold for known Providencia species. We therefore propose that these isolates be recognized as a novel species, Providencia xianensis sp. nov. Alarmingly, both strains, isolated from locations far apart, exhibited resistance to last-resort antibiotics, indicating their possible wide distribution, underscoring the urgency for immediate attention and enhanced surveillance for this emerging multidrug-resistant pathogen.
PubMed: 38714595
DOI: 10.1007/s10096-024-04821-y -
Bulletin of Entomological Research Oct 2023The honey bee is associated with a diverse community of microbes (viruses, bacteria, fungi, and protists), commonly known as the microbiome. Here, we present data on...
The honey bee is associated with a diverse community of microbes (viruses, bacteria, fungi, and protists), commonly known as the microbiome. Here, we present data on honey bee microbiota from two localities having different surrounding landscapes - mountain (the Rhodope Mountains) and lowland (the Danube plain). The bacterial communities of abdomen of adult bees were studied using amplicon sequencing of the 16S rRNA gene. The composition and dominance structure and their variability within and between localities, alpha and beta diversity, and core and differential taxa were compared at different hierarchical levels (operational taxonomic units to phylum). Seven genera (, , , , , , and ), known to include core gut-associated phylotypes or species clusters, dominated (92-100%) the bacterial assemblages. Significant variations were found in taxa distribution across both geographical regions and within each apiary. (Firmicutes) prevailed significantly in the mountain locality followed by and (Proteobacteria). Bacteria of four genera, core ( and ) and non-core ( and ), dominated the bee-associated assemblages of the Danube plain locality. Several ubiquitous bacterial genera (e.g., , , and ), some species known also as potential and opportunistic bee pathogens, had been found in the lowland locality. Beta diversity analyses confirmed the observed differences in the bacterial communities from both localities. The occurrence of non-core taxa contributes substantially to higher microbial richness and diversity in bees from the Danube plain locality. We assume that the observed differences in the microbiota of honey bees from both apiaries are due to a combination of factors specific for each region. The surrounding landscape features of both localities and related vegetation, anthropogenic impact and land use intensity, the beekeeping management practices, and bee health status might all contribute to observed differences in bee microbiota traits.
Topics: Animals; Bees; RNA, Ribosomal, 16S; Microbiota; Bacteria
PubMed: 37545319
DOI: 10.1017/S0007485323000378 -
Redox Biology Apr 2019Chronic hypobaric hypoxia during fetal and neonatal life induces neonatal pulmonary hypertension. Hypoxia and oxidative stress are driving this condition, which implies...
Chronic hypobaric hypoxia during fetal and neonatal life induces neonatal pulmonary hypertension. Hypoxia and oxidative stress are driving this condition, which implies an increase generation of reactive oxygen species (ROS) and/or decreased antioxidant capacity. Melatonin has antioxidant properties that decrease oxidative stress and improves pulmonary vascular function when administered postnatally. However, the effects of an antenatal treatment with melatonin in the neonatal pulmonary function and oxidative status are unknown. Therefore, we hypothesized that an antenatal therapy with melatonin improves the pulmonary arterial pressure and antioxidant status in high altitude pulmonary hypertensive neonates. Twelve ewes were bred at high altitude (3600 m); 6 of them were used as a control group (vehicle 1.4% ethanol) and 6 as a melatonin treated group (10 mg d melatonin in vehicle). Treatments were given once daily during the last third of gestation (100-150 days). Lambs were born and raised with their mothers until 12 days old, and neonatal pulmonary arterial pressure and resistance, plasma antioxidant capacity and the lung oxidative status were determined. Furthermore, we measured the pulmonary expression and activity for the antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase, and the oxidative stress markers 8-isoprostanes, 4HNE and nitrotyrosine. Finally, we assessed pulmonary pro-oxidant sources by the expression and function of NADPH oxidase, mitochondria and xanthine oxidase. Melatonin decreased the birth weight. However, melatonin enhanced the plasma antioxidant capacity and decreased the pulmonary antioxidant activity, associated with a diminished oxidative stress during postnatal life. Interestingly, melatonin also decreased ROS generation at the main pro-oxidant sources. Our findings suggest that antenatal administration of melatonin programs an enhanced antioxidant/pro-oxidant status, modulating ROS sources in the postnatal lung.
Topics: Animals; Animals, Newborn; Antioxidants; Biomarkers; Birth Weight; Blood Gas Analysis; Female; Gene Expression Regulation, Enzymologic; Glutathione; Heart Function Tests; Hypertension, Pulmonary; Melatonin; Oxidants; Oxidative Stress; Pregnancy; Reactive Nitrogen Species; Reactive Oxygen Species; Respiratory Function Tests; Sheep
PubMed: 30771751
DOI: 10.1016/j.redox.2019.101128